class_docstr: Test scatterplot.
class_docstr_tok: ["Test","scatterplot","."]
code: def test_top_words_remove_external_punctuation(self):
      s = pd.Series("stop. please!")
      s_true = pd.Series([1, 1], index=["please", "stop"])
      self.assertEqual(visualization.top_words(s).sort_index(), s_true)
  
file_path: texthero/tests/test_visualization.py
imports: import string
  import pandas
  import doctest
  from texthero import visualization
  from .None import PandasTestCase
label_desc: Use image node_id 7 for calling the TestVisualization obj's underlying member method code with example usage: obj.test_top_words_remove_external_punctuation() without return types